Æ·ol·i·pile, Æ·ol·i·pyle  n.  An apparatus consisting chiefly of a closed vessel (as a globe or cylinder) with one or more projecting bent tubes, through which steam is made to pass from the vessel, causing it to revolve. [Written also eolipile.]
  Note: ☞ Such an apparatus was first described by Hero of Alexandria about 200 years b. c. It has often been called the first steam engine.
  ◄ ►
  E·ol·i·pile n.  Same as æolipile.
  ◄ ►